@Nca78 Yes, I was actually thinking using DIP switch (or even more easy to read thumbwheel switch) to give a unique ID to each node! As soon as I receive the extra radio modules I ordered, I'll test that.
@Grubstake I'm afraid you're right! But it's ok to have just a few days of battery life. As I wrote, it might be often disassembled and reassembled.
The choice of MOSFET can be tricky. Seems that irlz44n was discontinued so you may need to find one adapted to the voltage and current you want to handle.
In all the cases you need to get a logic MOSFET too, meaning that they are fully open usually around 1 to 3V.
Also I'm sort of confused as it seems to me that L7812CV is a Voltage regulator, not a MOSFET. So if you are actually using that in the MOSFET spot it will definitively not work.
Especially if you are handling high current or voltage I would recommend using one from a reputable source for your MOSFET, I recently switched from mouser / digikey / aliexpress to mostly use http://www.arrow.com as you get free regular shipping, event if you order a couple of components (no affiliation to them whatsoever).
